Japanese patent application published under the number 1-173 502 discloses a headlight in which a spirit level is used to indicate the direction in which the reflector is pointing relative to the horizontal for the purpose of performing elevation adjustment on the beam. The spirit level is mounted on a body suitable for being removably installed behind the lamp base while the lamp is mounted in the reflector.
A drawback of this device lies in that the accuracy with which the direction is indicated relies on the accuracy with which the lamp is positioned in the lamp hole in the reflector. Thus, in the conventional case where fairly large clearance may exist between the reflector and the lamp, or where there may be poor positioning reproducibility from one lamp to another, in particular because of the manufacturing tolerances on lamp bases, the indication is given with insufficient accuracy.
The present invention seeks to minimize this inaccuracy by proposing a device in which the spirit level support is capable of bearing against the rear surface of the reflector.